As a method for controlling the gain in a broadcast receiver that receives broadcast waves with an antenna, a method shown in FIG. 8 is known, for example. FIG. 8 is a functional block diagram showing a partial configuration example of a receiver including a typical tuner, in which the tuner section is mainly discussed. As shown in FIG. 8, an RF input obtained from an antenna 101 is output to a demodulation circuit via a preamplifier 110, BPF 111, RFVGA 112, mixer 113, BPF 115, and IF amplifier 116 of a tuner section 108. The mixer 113 is provided with an oscillator (OSC) 114. The output of the IF amplifier 116 is also provided to a level detector 125, so that it is fed back to the RFVGA 112 via voltage control means 126.
There is also known a technique described in Patent Document 1 below. According to this technique, a receiver system is provided that includes an antenna whose frequency tuning is adjustable with a matching circuit, an RF circuit that amplifies an RF signal received by the antenna and converts the frequency of the signal, a digital processor that converts the received analog signal output from the RF circuit into a digital signal, and a CPU that supplies a tuning control signal to the matching circuit to control the frequency tuning of the antenna, in which a gain control signal for the antenna is generated based on the power or amplitude information on the received signal, and such a gain control signal is added to the tuning control signal.    Patent Document 1: JP Patent Publication (Kokai) No. 2004-363854